Standard Test Method for Bulk Solids Using Schulze Ring Shear Tester

Importancia y uso:

5.1 Reliable, controlled flow of bulk solids from bins and hoppers is essential in almost every industrial facility. Unfortunately, flow stoppages due to arching and ratholing are common. Additional problems include uncontrolled flow (flooding) of powders, segregation of particle mixtures, usable capacity which is significantly less than design capacity, caking and spoilage of bulk solids in stagnant zones, and structural failures.

5.2 By measuring the flow properties of bulk solids, and designing bins and hoppers based on these flow properties, most flow problems can be prevented or eliminated (1).3

5.3 For bulk solids with a significant percentage of particles (typically, one third or more) finer than about 6 mm (¹/₄ in.), the unconfined yield strength is governed by the fines (−6 mm fraction). For such bulk solids, strength and wall friction tests may be performed on the fine fraction only.

Note 1: The quality of the result produced by this standard is dependent on the competence of personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself ensure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors. Practice D3740 was developed for agencies engaged in the testing or inspection (or both) of soil and rock. As such it is not totally applicable to agencies performing this standard. However, users of this standard should recognize that the framework of Practice D3740 is appropriate for evaluating the quality of an agency performing this standard. Currently there is no known qualifying national authority that inspects agencies that perform this standard.

Subcomité:

D18.24

Referida por:

D7891-24, D8081-17R21E01

Volúmen:

04.09

Número ICS:

59.080.01 (Textiles in general)

Palabras clave:

bulk solid; effective angle of friction; effective yield locus; flow function; flowability; Jenike Shear Cell; internal friction angle; kinematic wall friction angle; powder; Schulze Ring Shear Tester; translational shear tester; unconfined yield strength; wall friction;